Search Publications
Modeling of geocoronal solar wind charge exchange events detected with Suzaku
Miyoshi, Yoshizumi; Ezoe, Yuichiro; Ishikawa, Kumi +2 more
A model of geocoronal solar wind charge exchange (SWCX) emission was built and compared to five Suzaku detections of bright geocoronal SWCX events. An exospheric neutral hydrogen distribution model, charge exchange cross-sections, solar wind ion data taken with the ACE and WIND satellites, and magnetic field models of the Earth's magnetosphere are…
TU Tau B: The Peculiar "Eclipse" of a Possible Proto-barium Giant
Walker, Gary; Gray, Richard O.; Corbally, Christopher J. +26 more
TU Tau (=HD 38218 = HIP 27135) is a binary system consisting of a C-N carbon star primary and an A-type secondary. We report on new photometry and spectroscopy which tracked the recent disappearance of the A-star secondary. The dimming of the A star was gradual and irregular, with one or more brief brightenings, implying the presence of nonhomogen…
Classifying Interplanetary Discontinuities Using Supervised Machine Learning
Munteanu, Costel; Dumitru, Daniel
Directional discontinuities (DDs) are defined as abrupt changes of the magnetic field orientation. We use observations from ESA's Cluster mission to compile a database of events: Four thousand two hundred and sixteen events are identified in January-April 2007, and 5,194 in January-April 2008. Localized time scale images depicting angular changes …
Physical and Kinematical Characteristics of Wolf-Rayet Central Stars and their Host Planetary Nebulae
Ali, A.; Awad, Z.
We address the physical and kinematical properties of Wolf-Rayet [WR] central stars (CSs) and their host planetary nebulae (PNe). The studied sample comprises all [WR] CSs that are currently known. The analysis is based on recent observations of the parallax, proper motion, and color index of [WR] CSs from the Gaia space mission's early third rele…
Investigation of Stellar Kinematics and Ionized Gas Outflows in Local (U)LIRGs
Kilerci, Ece; Wang, Shu; Zou, Fan +4 more
We explore the properties of stellar kinematics and ionized gas in a sample of 1106 local (U)LIRGs from the AKARI telescope. We combine data from Wide-field Infrared Survey Explorer and Sloan Digital Sky Survey Data Release 13 to fit the spectral energy distribution (SED) of each source to constrain the contribution of active galactic nuclei (AGNs…
Exploring the evidence of Middle Amazonian aquifer sedimentary outburst residues in a Martian chaotic terrain
Kargel, Jeffrey S.; Berman, Daniel C.; Rodriguez, J. Alexis P. +7 more
The quest for past Martian life hinges on locating surface formations linked to ancient habitability. While Mars' surface is considered to have become cryogenic ~3.7 Ga, stable subsurface aquifers persisted long after this transition. Their extensive collapse triggered megafloods ~3.4 Ga, and the resulting outflow channel excavation generated vol…
Catalog of Integrated-light Star Cluster Light Curves in TESS
Davenport, James R. A.; Pepper, Joshua; Fetherolf, Tara +10 more
We present the first integrated-light, TESS-based light curves for star clusters in the Milky Way, Small Magellanic Cloud, and Large Magellanic Cloud. We explore the information encoded in these light curves, with particular emphasis on variability. We describe our publicly available package elk, which is designed to extract the light curves by ap…
Comparison of distance measurements to dust clouds using GRB X-ray haloes and 3D dust extinction
Tiengo, A.; Bošnjak, Ž.; Pintore, F. +3 more
X-ray photons from energetic sources such as gamma-ray bursts (GRBs) can be scattered on dust clouds in the Milky Way, creating a time-evolving halo around the GRB position. X-ray observations of such haloes allow the measurement of dust cloud distances in the Galaxy on which the scattering occurs. We present the first systematic comparison of the…
A colourful analysis: Probing the eclipse of the black hole and central engine in NGC 6814 using X-ray colour-colour grids
Miller, J. M.; Gallo, L. C.; Gonzalez, A. G. +1 more
Eclipsing of the X-ray emitting region in active galactic nuclei (AGN) is a potentially powerful probe to examine the AGN environment and absorber properties. Here, we study the eclipse data from the 2016 XMM-Newton observation of NGC 6814 using a colour-colour analysis. Colours (i.e. hardness ratios) can provide the advantage of better time resol…
Light and colour of cirrus, translucent, and opaque dust in the high-latitude area of LDN 1642
Haas, M.; Väisänen, P.; Lehtinen, K. +2 more
We have performed a 5-colour surface photometric study of the high-galactic-latitude area of dark nebula LDN 1642. Scattered light properties are presented of diffuse, translucent, and opaque dust over the range of 3500-5500 Å . Far infrared absolute photometry at 200 µm improves the precision of and provides a zero point to the extinction. The in…